Dovetail-cutter



(No Model.)

. A. G. MEAD.

DOVETAIL GUTTER.

No.` 479,975. Patented July 19, 1892.

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aTnNT ALBERT G. MEAD, OF BOSTON, MASSACHUSETTS.

DOVETAlL-CUTTER.

SPECIFICATION forming part of Letters Patent No. 479,075, dated July 19, 1892.

Application filed February 17l 1892. Serial No. 421,839. (No model.)

To all whom. it' may concern:

Be it known that I, ALBERT G. MEAD, of Boston, county of Suffolk, and Commonwealth of Massachusetts, have invented certain new and useful Improvements in Dovetail-Cutters, of which the following is a full specification.

My invention relates to cutters for dovetailing; and it consists of a conical tool capable of being sharpened and readily adjusted in place, being constructed as hereinafter described in detail.

Referring to the accompanying drawings, Figure l shows in perspective my improved cutter complete. Fig. 2 is a plan view of the cutting end thereof. Fig. 3 is a central longitudinal section of the plane of o: Fig. 2. Fig. 4 is a plan view of the outer end of the cutter-socket with the knife removed, and Fig. 5 shows in perspective the conical cutter-knife.

A is the shank of the cutter-holder,having at one end the screw-threaded portion A2, whereby the cutter is connected to the revolving spindle of the machine.

A is the conical knife-holding socket, the outside surface of which is concentric with the axis of the screw A2, and hence with the axis of rotation of the spindle. The conical interior surface of the socket A is, however, eccentric with the exterior thereof, as plainly shown in Fig. 4, so that, as shown in Figs. l and 4, an opening is left along one side thereof.

B is the cutter-knife, which is conical and of a size to it the conical interior of the socket, and C is a centrally-bored-out conical plug of a size to fit the interior of the cutter-knife. The cutter-knife is open along one side and provided with a sharpened cutting-edge b, beveled on the inside, as shown, so that the outside surface of the knife is smooth and circular. The knife is provided at its outer end with the sharp horizontal cutting-lip b integral therewith, which when the knife is in place in the socket projects beyond the socket and makes a fine thin cut at the bottom of the dovetail in advance of the cutter, thereby preventing the wood from chipping and insuring a clean well-deiined cut. The shank of the socket is bored out from the inside at D', with a tapped hole in the center of the interior opening in the socket, and thus .eccentric with the spindle. This hole is of sufficient size to contain within it the screw D, which passes through the conical plug O and yholds the cutter-knife in place. The plug is provided with the projection c, which Vfits a depression c in the socket, and thus prevents the plug Ofrom turning, or, in other words, locks it in place.

When fixed in place, the sharp edge b of the cutter-knife projects beyond the edge ct of the socket to a greater or less degree, as desired, the amount of the lead thus xed determining the size of cut madeby the tool as it revolves. Since the cutter-knife is held eccentric to the spindle and to the outside of the socket A', the size of cut made bythe tool is varied readily by varying the lead of the knife-edge b beyond the edge a.

By simply loosening the screw D the position of the cutter-knife is readily changed, and'when once the proper lead of the cuttingedge is determined it is a very easy matter to remove and sharpen the knife when dull and to replace it with the same lead as before.

The knife-blade being in the shape of an open hollow cone, the sides of which are of uniform thickness all around, it will last for a very long time, since by reason of its peculiar shape three-quarters or more of its Inaterial may be worn away by sharpening without impairing its use, as will readily be seen.

I claiml. In a dovetail-cutter, a conical knife-holding socket with the axis of rotation of which the conical exterior surface of said socket is concentric and the conical interior eccentric, whereby the socket isl open along one side, in combination with an open hollow conical cutting-knife, a conical plug, and a fasteningscrew, all constructed and arranged substantially as described.

2. In a dovetail-cutter, the combination, with an open hollow conical knife-holding socket, of an open hollow conical cuttingknife, suitably clamped within said socket eccentric with the axis of rotation, whereby the size of the cut may be varied by the lead of the sharpened knife-edge beyond the edge of the socket, substantially as described.

8. In a dovetail-cutter, an open hollow coni- IOO plug C, provided with the projection c, engaging with a depression in the inner end of said socket, and the fasteningscrew D, all 15 constructed and arranged substantially as v and for the purposes described.

In witness whereof I have hereunto set my hand.

ALBERT G. MEAD.

fitnesscez WM. W. II. Dowsn, ALBERT E. LEACH. 

